[INFO] fetching crate prefix-map 0.3.1...
[INFO] testing prefix-map-0.3.1 against 1.55.0 for beta-1.56-1
[INFO] extracting crate prefix-map 0.3.1 into /workspace/builds/worker-38/source
[INFO] validating manifest of crates.io crate prefix-map 0.3.1 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate prefix-map 0.3.1
[INFO] finished tweaking crates.io crate prefix-map 0.3.1
[INFO] tweaked toml for crates.io crate prefix-map 0.3.1 written to /workspace/builds/worker-38/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9eee6c9acfa7608246f46073c383fc6d33af9a87ff2f1840c30f938decf22c48
[INFO] running `Command { std: "docker" "start" "-a" "9eee6c9acfa7608246f46073c383fc6d33af9a87ff2f1840c30f938decf22c48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9eee6c9acfa7608246f46073c383fc6d33af9a87ff2f1840c30f938decf22c48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9eee6c9acfa7608246f46073c383fc6d33af9a87ff2f1840c30f938decf22c48", kill_on_drop: false }`
[INFO] [stdout] 9eee6c9acfa7608246f46073c383fc6d33af9a87ff2f1840c30f938decf22c48
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a5f16e2ab9e3e2bc2394c40bb10bac428b233731d68f9f78db0d58940320d2fa
[INFO] running `Command { std: "docker" "start" "-a" "a5f16e2ab9e3e2bc2394c40bb10bac428b233731d68f9f78db0d58940320d2fa", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling unicode-segmentation v0.1.3
[INFO] [stderr]    Compiling prefix-map v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(associated_type_defaults, iter_arith, test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the trait bound `<Self as ToOwned>::Owned: OwnedPrefix` is not satisfied
[INFO] [stdout]   --> src/prefix.rs:14:5
[INFO] [stdout]    |
[INFO] [stdout] 14 |       type OwnedPrefix: OwnedPrefix<Item=Self::OwnedItem> + Borrow<Self> =
[INFO] [stdout]    |       ^                 --------------------------------- required by this bound in `ToPrefix::OwnedPrefix`
[INFO] [stdout]    |  _____|
[INFO] [stdout]    | |
[INFO] [stdout] 15 | |         <Self as ToOwned>::Owned;
[INFO] [stdout]    | |_________________________________^ the trait `OwnedPrefix` is not implemented for `<Self as ToOwned>::Owned`
[INFO] [stdout]    |
[INFO] [stdout] help: consider further restricting the associated type
[INFO] [stdout]    |
[INFO] [stdout] 11 | pub trait ToPrefix: ToOwned where <Self as ToOwned>::Owned: OwnedPrefix {
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0275]: overflow evaluating the requirement `<Self as ToPrefix>::OwnedItem == _`
[INFO] [stdout]   --> src/prefix.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 | /     type OwnedItem: Borrow<Self::BorrowedItem> + Clone + Ord =
[INFO] [stdout] 20 | |         <Self::OwnedPrefix as OwnedPrefix>::Item;
[INFO] [stdout]    | |_________________________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0275, E0277, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0275`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `prefix-map` due to 4 previous errors
[INFO] running `Command { std: "docker" "inspect" "a5f16e2ab9e3e2bc2394c40bb10bac428b233731d68f9f78db0d58940320d2fa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a5f16e2ab9e3e2bc2394c40bb10bac428b233731d68f9f78db0d58940320d2fa", kill_on_drop: false }`
[INFO] [stdout] a5f16e2ab9e3e2bc2394c40bb10bac428b233731d68f9f78db0d58940320d2fa